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 # Summary
 
-AdditiveFOAM is a computational framework that simulates transport phenomena in Additive Manufacturing (AM) processes, built on OpenFOAM [@openfoam], the leading free, open-source software package for computational fluid dynamics (CFD). OpenFOAM offers an extensible platform for solving complex multiphysics problems using state-of-the-art finite volume methods. AdditiveFOAM utilizes the capabilities of OpenFOAM to develop specialized tools aimed at addressing challenges in AM processing.
+AdditiveFOAM is a computational framework that simulates transport phenomena in Additive Manufacturing (AM) processes. It is built on OpenFOAM [@openfoam], the leading free, open-source software package for computational fluid dynamics (CFD). OpenFOAM offers an extensible platform for solving complex multiphysics problems using state-of-the-art finite volume methods. AdditiveFOAM leverages these capabilities to develop specialized tools aimed at addressing challenges in AM processing.
 
-Metal additive manufacturing, also known as metal 3D printing, is an advanced manufacturing technique that creates physical parts from a three-dimensional (3D) digital model by melting metal powder or wire feedstock. A significant area of research in metal AM is focused on process planning to mitigate anomalous features during printing that are deleterious to part performance (e.g. porosity and cracking), as well as controlling localized microstructure and material properties. Given the high costs and substantial time requirements associated with experimental methods for qualifying new materials and processes, there is a compelling incentive for researchers to utilize advanced numerical models. In this context, AdditiveFOAM offers modeling capabilities to better understand undesirable features in printing, thereby enhancing process planning and reducing the reliance on labor-intensive experimental campaigns.
+Metal additive manufacturing, also known as metal 3D printing, is an advanced manufacturing technique that creates physical parts from a three-dimensional (3D) digital model by melting metal powder or wire feedstock. A significant area of research in metal AM focuses on process planning to mitigate anomalous features during printing that are deleterious to part performance (e.g., porosity and cracking), as well as controlling localized microstructure and material properties. Given the high costs and substantial time requirements associated with experimental methods for qualifying new materials and processes, there is a compelling incentive for researchers to utilize advanced computational simulations. In this context, AdditiveFOAM offers a simulation framework to better understand undesirable features in printing, thereby enhancing process planning and reducing the reliance on labor-intensive experimental campaigns.
 
 # Statement of need
 
-Numerical models for AM traditionally seek to represent physics at a single length scale depending on the target question. Two main categories of models with available software solutions are distinguished: 1) high-fidelity melt pool-scale models, and 2) part-scale heat transfer models. 
+Numerical models for AM traditionally seek to represent physics at a single length scale depending on the target question. Two main categories of models with available software solutions are distinguished: 1) high-fidelity melt pool-scale models, and 2) part-scale heat transfer models.
 
-The first category contains models which seek to resolve all relevant physics within the melt pool. These models can produce excellent agreement with experiments and offer insights into the underlying causes of anomalous features during processing, but are generally expensive to run, limiting the scan length that can be simulated to a few millimeters with current computational resources. Due to their computational expense, these models are well-suited for use at specialized research institutions with large HPC infrastructure to answer target questions about melt pool scale physical phenomena. An exhaustive review of high-fidelity melt pool models is beyond the current scope of this article; however, two primary software packages are highlighted: 
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-- ALE3D [@ALE3D] is a versatile multiphysics simulation tool that uses the Arbitrary Lagrangian-Eulerian approach and has been used for powder-resolved simulations of laser-material interactions in AM. However, ALE3D is a limited access code for use by DoD and DOE laboratories and their contractors and ALE3D4I is available for U.S. companies and academics through individual use agreements. 
-
-- FLOW-3D [@FLOW-3D] is a commercial CFD software known for its capabilities in simulating complex free-surface problems, and has several specialized models for AM. However, the Flow-3D is proprietary, meaning its source code is not available for public inspection or modification and users must purchase a license to use the software. 
+The first category contains models that seek to resolve all relevant physics within the melt pool. These models can produce excellent agreement with experiments and offer insights into the underlying causes of anomalous features during processing, but are generally expensive to run, limiting the scan length that can be simulated to a few millimeters with current computational resources. Due to their computational expense, these models are well-suited for use at specialized research institutions with large HPC infrastructure to answer target questions about melt pool scale physical phenomena. For example, ALE3D [@ALE3D] is a versatile multiphysics simulation tool that uses the Arbitrary Lagrangian-Eulerian approach and has been used for powder-resolved simulations of laser-material interactions in AM. However, ALE3D is a limited access code for use by United States Department of Defense/Energy laboratories and their contractors, while ALE3D4I is available for U.S. companies and academics through individual use agreements. Alternatively, FLOW-3D [@FLOW-3D] is a commercial CFD software known for its capabilities in simulating complex free-surface problems, and it has several specialized models for AM. However, FLOW-3D is proprietary, meaning its source code is not available for public inspection or modification, and users must purchase a license to use the software.
 
 The second category contains models that simplify melt pool physics to rapidly simulate heat transport, residual stress, and distortion across an entire part. Commercial finite element thermomechanics software solutions built on Abaqus [@abaqus] and Ansys [@ansys] are available; however, these software packages are not open and free to use and develop upon. Alternatively, Adamantine [@adamantine] is a thermomechanics simulation tool built on an open-source software stack designed for high-performance computing across various architectures, including the deal.II finite element software package [@deal.ii], providing an alternative to proprietary software solutions.
 
 There is an established need for intermediate frameworks that accurately predict melt pool shape, thermal gradients, and other meso-scale quantities across an entire part. These models can inform process design decisions through heuristic estimations of anomalous printing features (e.g., keyhole formation and lack-of-fusion) and predict the final microstructure and material properties of AM components. AdditiveFOAM addresses these challenges, featuring a volumetric source term in the energy equation for multiple heat sources, optional Marangoni-driven fluid flow, and a scheme for implementing tabulated thermodynamic pathways for metal alloys.
 
 # Software Features
-The main feature of AdditiveFOAM is a transient, multiphysics application which solves conservation equations for mass, momentum, and energy during AM processing, built upon on the OpenFOAM finite volume software package [@openfoam]. This solver includes a novel thermodynamic algorithm enabling variable-order time integration for tabulated thermodynamic pathways. The available time integration schemes are explicit forward Euler, implicit backward Euler, backward differentiation formula (BDF-2), and Crank-Nicolson. An adaptive time integration and time-stepping method automatically switches between implicit and explicit schemes to balance the computational cost and solution accuracy depending on the problem state and user-defined tolerances. Additionally, AdditiveFOAM features boundary conditions for Marangoni-driven fluid flow in the melt pool as well as convective and radiative heat transfer. Another feature of AdditiveFOAM is the volumetric heat source library that supports any number of independently moving sources with distinct energy profiles that have been validated for several AM processes including laser powder bed fusion (LPBF), directed energy deposition (DED), and electron beam melting (EBM). Finally, AdditiveFOAM leverages existing OpenFOAM libraries to sample thermal data needed for microstructure predictions with a specific library for coupling to the grain structure prediction software ExaCA [@exaca]. Future releases of AdditiveFOAM will focus on resource-optimized adaptive mesh refinement (AMR), dynamic load-balancing using the Zoltan [@zoltan] library, and the integration of next-generation laser profiles (e.g., nLight AFX series) into the volumetric heat source library.
+The main feature of AdditiveFOAM is a transient, multiphysics application that solves conservation equations for mass, momentum, and energy during AM processing, built upon the OpenFOAM finite volume software package [@openfoam]. This solver includes a novel thermodynamic algorithm enabling variable-order time integration for tabulated thermodynamic pathways. The available time integration schemes are explicit forward Euler, implicit backward Euler, backward differentiation formula (BDF-2), and Crank-Nicolson. An adaptive time integration and time-stepping method automatically switches between implicit and explicit schemes to balance computational cost and solution accuracy depending on the problem state and user-defined tolerances. Additionally, AdditiveFOAM features boundary conditions for Marangoni-driven fluid flow in the melt pool, as well as convective and radiative heat transfer. Another feature of AdditiveFOAM is the volumetric heat source library that supports any number of independently moving sources with distinct energy profiles that have been validated for several AM processes, including laser powder bed fusion (LPBF), directed energy deposition (DED), and electron beam melting (EBM). Finally, AdditiveFOAM leverages existing OpenFOAM libraries to sample thermal data needed for microstructure predictions with a specific library for coupling to the grain structure prediction software ExaCA [@exaca]. Future releases of AdditiveFOAM will focus on resource-optimized adaptive mesh refinement (AMR), dynamic load-balancing using the Zoltan [@zoltan] library, and the integration of next-generation laser profiles (e.g., nLight AFX series) into the volumetric heat source library.
 
-AdditiveFOAM was designed to be used openly by researchers, industry, and academics. It has already been used in a number of scientific publications primarily focused on studying how AM process planning influences the development of local microstructural features in a part. Select publications that demonstrates AdditiveFOAM’s usage towards understanding the connection between process planning and microstructure evolution in metal AM include: 
+AdditiveFOAM was designed to be used openly by researchers, industry, and academics. It has already been used in several scientific publications primarily focused on studying how AM process planning influences the development of local microstructural features in a part. Select publications that demonstrate AdditiveFOAM’s usage towards understanding the connection between process planning and microstructure evolution in metal AM include:
 
 - Knapp et al. [@knapp] developed an automated framework for statistical calibration of the gaussian heat source parameters available in AdditiveFOAM to accurately predict the melt pool shape, solidification conditions, and solidification grain structure for single track welds on IN625 plate.